I'm not a "paleo" guy or whatever it is, but I'm confident that there is ~5x more sugar (2-3g vs 11-12g) in a sweet potato than a red potato of equal size.

For glycogen replenishment, any type of potato is great due to the high starch content in white, red, and sweet potatoes. Sweet potatoes have a comparatively higher vitamin content, but also have a little but more naturally occurring fructose and sucrose than other varieties.

But again, any potato would be a great choice here -- GI index can suck one

Tubers are generally accepted for refeeds under Paleo diet. They're high in potassium and alkalinic. What makes them different from other forms of complex carbs is that they do not have gluten or lectins.